Notably, most current covalent CDK12/13 inhibitors are structurally derived from the CDK7 covalent inhibitor THZ1, which targets a similar cysteine residue in the structure (Cys312).17, 30 Developing new irreversible inhibitors with alternative chemical scaffolds is highly desirable for further validating selective CDK12/13 inhibition as a viable cancer therapeutic strategy. The gene discussed is CDK12; the disease is cancer.